fix: await on redisClient.connect()

.connect() is an async function so any errors just get lost (and we may
end up stuck loading a page). This change makes the page fail fast
and show error page.

index.js

@@ -19,7 +19,7 @@ dotenv.config()
 const app = express()
 
 setupMiddlewares(app)
-setupSession(app)
+await setupSession(app)
 setupNunjucks({ app, dataSubjects })
 setupRoutes(app)
 setupSentry(app)

src/serverSetup/session.js

@@ -5,7 +5,7 @@ import cookieParser from 'cookie-parser'
 import config from '../../config/index.js'
 import logger from '../utils/logger.js'
 
-export function setupSession (app) {
+export async function setupSession (app) {
   app.use(cookieParser())
   let sessionStore
   if ('redis' in config) {
@@ -16,7 +16,7 @@ export function setupSession (app) {
     const errorHandler = (err) => {
       logger.error(`session/setupSession: redis connection error: ${err.code}`)
     }
-    redisClient.connect().catch(errorHandler)
+    await redisClient.connect().catch(errorHandler)
 
     sessionStore = new RedisStore({
       client: redisClient